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1.
Groundwater was being remediated with pump and treat technology at a facility where the groundwater was contaminated with commonly used degreaser solvents. Hydraulic conductivity of the heterogeneous residuum was beneficiated by applying pneumatic fracturing technology. The remedial system was controlled and monitored by a sophisticated remote telemetry system. A case history follows.  相似文献   
2.
Incinerator bottom ash (IBA) is a residual produced from incinerating municipal solid waste. In the past, IBA presented a big waste disposal problem; however, various recycling approaches have been adopted in recent years to mitigate this problem, as well as to provide a useful alternative to using primary aggregate resources. The use of IBA as an alternative to conventional aggregates in different civil engineering construction applications helps to conserve premium grade aggregate supplies; however, when IBA is in contact with water in the field, as a consequence of precipitation events or changes in water table, elements, such as salts and heavy metals, may be released to the soil and ground water. In this work, IBA waste was mixed with limestone aggregate to produce a blend with acceptable mechanical properties and minimum environmental risks for use as road foundation. The study focused on evaluating potential environmental impacts of some constituents, including sulphate, chloride, sodium, copper, zinc and lead in IBA blends using a lysimeter as a large scale leaching tool. Moreover, a specific scenario simulating field conditions was adopted in the lysimeter to assess the potential impact of changing conditions, such as IBA content in the blend, liquid to solid ratio (L/S) and pH value, on long-term release of heavy metals and salts. Then, numerical modelling was used to predict the release of the aforementioned constituents from IBA based on initial measurement of intrinsic material properties and the kinetic desorption process concept. Experimental results showed that zinc and lead were released in very low concentrations but sodium and sulphate were in high concentrations. The control limestone only blend also demonstrated low release concentrations of constituents in comparison to IBA blends, where constituent concentrations increased with increase in IBA content. Experimental results were compared with numerical results obtained using a non-equilibrium desorption model. Good agreement was found between the two sets of data.  相似文献   
3.
Geochemical and geostatistical study of the chromium concentration in groundwater occurring at variable depths of 12 to 33.5 m (40 to 110 ft) in the Karachi urban area of Pakistan have been made. Samples were collected at variable distances, with a maximum of 1 km interval, on the bases of population, industries, types, and density. The chromium concentration has also been worked out to deduce the threshold value of the area under study and the estimation of probability impact modeling, in terms of concentration variation, by using the disjunctive kriging technique. The outcome of the present work appears to be a good tool to decipher pollution variation in the groundwater of highly urbanized areas, with respect to the population and industries. The patterns of distribution of chromium concentration in groundwater and pollution hotspots in particular localities appear to be more related to the types of industries than to the effect of population types.  相似文献   
4.
Environmental Science and Pollution Research - Phosphorus is an essential macro-mineral nutrient for poultry, needed for the body growth, development of bones, genomic function, good...  相似文献   
5.
Environmental Science and Pollution Research - The present study was undertaken to appraise the efficacy of exogenous taurine in alleviating boron (B) and chromium (Cr) toxicity. Taurine protects...  相似文献   
6.
India is among the 23 nations around the globe where health problems occur due to excess ingestion of fluoride (>1.5 mg/l) by drinking water. In Rajasthan, 18 out of 32 districts are fluorotic and 11 million of the populations are at risk. An exploratory qualitative survey was conducted to describe perception of the community regarding fluoride and related health problems in Central Rajasthan. A study on distribution and health hazards by fluoride contaminate in groundwater was performed in 1,030 villages of Bhilwara district of Central Rajasthan. One thousand thirty water samples were collected and analyzed for fluoride concentration. Fluoride concentration in these villages varies from 0.2 to 13.0 mg/l. Seven hundred fifty-six (73.4%) villages have fluoride concentration above 1.0 mg/l. Sixty (5.83%) villages have fluoride concentration above 5.0 mg/l with maximum numbers (24, 19.5%) from Shahpura tehsil. A detailed fluorosis study was carried out in 41 villages out of 60 villages having fluoride above 5.0 mg/l in the study age, sex, and occupation data were also collected. Four thousand, two hundred fifty-two individuals above 5 years age were examined for the evidence of dental fluorosis, while 1998 individuals above 21 years were examined for the evidence of skeletal fluorosis. The overall prevalence of dental and skeletal fluorosis was found to be 3,270/4,252 (76.9%) and 949/1,998 (47.5%), respectively. Maximum of 23.9% (1,016) individuals have mild grade of Dean’s classification. Three hundred seventy-four (8.8%) individuals have severe type of dental fluorosis. The Dean’s Community Fluorosis Index for the studied area in total is 1.62. Maximum CFI 3.0 was recorded from Surajpura of Banera Tehsil. Five hundred sixty-six (28.3%) individuals have Grade I type of skeletal fluorosis while only 0.6% (12) individuals have Grade III skeletal fluorosis. In conclusion, the prevalence and severity of fluorosis increased with increasing fluoride concentration. It was interesting to note that in some villages, the prevalence and severity of fluorosis were highest in subjects belonging to the economically poor community. Similarly, male laborers showed highest prevalence of fluorosis. Prevalence and severity of fluorosis were observed higher in subjects using tobacco, bettle nuts, and alcoholic drinks. In contrast, subjects using citrus fruits and having good nutritional status showed low prevalence.  相似文献   
7.
Field experiments were carried out during 1996–97at Gulawathi, Muthiani and Salarpur Villages, IARI Farm, NewDelhi and NCPP Campus, Dadri to evaluate changes in soilcharacteristics and growth of wheat (Triticum aestivum L.),mustard (Brassica juncea L.), lentil (Lence esculentaMoench.), rice (Oryza sativa L.) and maize (Zea mays L.) byvarying amounts of flyash addition (up to 50t ha-1) in soils atsowing/transplanting time of crops. Flyash addition in areasadjoining NCPP Thermal Power Plant, Dadri, Ghaziabad, U.P.ranged from 5–12 t ha-1 yr-1 in 1995–96. Shoot and root growthand yield of test crops at different locations after flyashincorporation resulted in beneficial effects of flyashaddition in most cases. The silt dominant texture of flyashimproved loamy sand to sandy loam textures of the surfacesoils at the farmers' fields. The increased growth in yield ofcrops with flyash incorporation was possibly due tomodifications in soil moisture retention and transmissioncharacteristics, bulk density, physico-chemical characterssuch as pH and EC and organic carbon content. The response offlyash addition in the soil on soil health and cropproductivity needs to be evaluated on long-term sustainableaspects.  相似文献   
8.
We investigated selected chlorinated pollutants (β-HCH, γ-HCH, DDDs, DDEs, o,p′-DDT, p,p′-DDT, heptachlor, aldrin, dieldrin, and endrin) in the Lahore and the Sialkot districts of Pakistan, using eggs of cattle egret (Bubulcus ibis) collected during May and June 2007. The pollutant with highest level and frequency was ΣDDT, followed by β-HCH, γ-HCH, heptachlor, aldrin, dieldrin, and endrin in descending order. The concentration(s) were significantly higher in Sialkot heronry for all the pollutants (except p,p′-DDT) than in Lahore. The values for DDTs, β-HCH, γ-HCH, and heptachlor were significantly higher (p < 0.05) in the egg(s) than in sediment(s) and in the chicks’ diet, due to biomagnification. Among DDTs analogues, p,p′-DDD was the major contaminant with >60 % of total DDT burden, reflecting the widespread aged as well as recent use of DDT as well as anaerobic degradation (DDD/DDE > 1 in many cases) in the nearby paddy soils. In few samples, p,p′-DDT/(DDD + DDE) > 0.5 suggested the recent emission patterns from surrounding contaminated areas of demolished DDT units and obsolete pesticide stores. The higher levels of HCHs (i.e., β-HCH) in the samples collected from Sialkot indicate exposure from long-term agricultural use. Overall, concentrations of all studied POPs were less than the threshold levels known to affect reproduction. Nevertheless, total DDTs and/or HCHs burdens in some eggs contained concentrations of greater than what would educe adverse effects on birds. This is among few studies on OCPs exposure to avian species, which provide the evidence of Pakistan’s contribution toward the Global POPs emission.  相似文献   
9.
The present study describes the estimation of particulate matter (cotton dust) with different sizes, i.e., PM(1.0), PM(2.5), PM(4.0), and PM(10.0 μm) in small-scale weaving industry (power looms) situated in district Hafizabad, Punjab, Pakistan, and the assessment of health problems of workers associated with these pollutants. A significant difference was found in PM(1.0), PM(2.5), PM(4.0), and PM(10.0) with reference to nine different sampling stations with p values <0.05. Multiple comparisons of particulate matter with respect to size, i.e. PM(1.0), PM(2.5), PM(4.0), and PM(10.0), depict that PM(1.0) differs significantly from PM(2.5), PM(4.0), and PM(10.0), with p values <0.05 and that PM(2.5) differs significantly from PM(1.0) and PM(10.0), with p values <0.05, whereas PM(2.5) differs non-significantly from PM(4.0), with a p value >0.05 in defined sampling stations on an average basis. Majority of the workers were facing several diseases due to interaction with particulate matter (cotton dust) during working hours. Flue, cough, eye, and skin infections were the most common diseases among workers caused by particulate matter (cotton dust).  相似文献   
10.

This study is trying to explore the relationship between corporate social responsibility (CSR) disclosures and financial performances (FP) through mediating role of the employee productivity (EP). This study classifies the CSR performances into four contexts, for instance, environment social governance (ESG), environmental improvement activity scores of CSR, social welfare activity score, and governance structure improvement score. The banking performance is classified into three different aspects such as returns on assets (ROA), returns on equity (ROE), and nominal interest margin profit (NIMP). The study covers the data set start from 2008 to 2019 regarding thirty commercial banks of China. The study uses the linear, non-linear, and quadratic techniques to explore the association between CSR disclosures and banking performances. The linear model result shows that the governance score is significant influencing the banking performance. Moreover, the employee productivities are also positive significant affecting the baking performances. The non-linear results of model show that composite score of ESG with employee productivity has significant influence on financial performance.

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